Taking care of your Wusthof knives is important. This universal Wusthof knife sharpener features four stages, two stages for standard knives and two stages for Asian knives. The first stage, carbide, is coarse for sharpening dull knife edges. The second stage, ceramic, is fine for honing and finishing the edge after sharpening. Safe and easy to use, this hand held knife sharpener requires nothing but a few easy strokes to keep blades sharp. The Wusthof Universal Knife Sharpener can be used to restore a factory edge to any knife in your collection, including those with a PEtec edge and serrated or wavy knife blades.